On 5/24/18 9:03 PM, Heinrich Schuchardt wrote: > Hello Michael, > > in the mmap(2) man page MAP_ANON is described as deprecated. > > When I look at the NetBSD manpage > http://netbsd.gw.com/cgi-bin/man-cgi?mmap+2+NetBSD-current > I found that MAP_ANONYMOUS is not defined. > > https://www.dragonflybsd.org/cgi/web-man?command=mmap§ion=2 > indicates MAP_ANONYMOUS is an alias for MAP_ANON and is provided for > compatibility. > > https://man.openbsd.org/mmap.2 also knows MAP_ANONYMOUS as a synonym. > > https://www.unix.com/man-page/osx/2/mmap/ does not know MAP_ANONYMOUS. > > So shouldn't the man page indicate that MAP_ANON is to be favored to > write portable code? And correspondingly mark MAP_ANONYMOUS as synonym > only kept for compatibility. > > The Open Group Base Specifications Issue 7, 2018 Edition does not > reference either of both. So both values are not POSIX but it is not > correct to describe them as Linux only. The text saying that MAP_ANON is deprecated is ancient (at least 20 years old). I don't know why that text was added. Things are not simple though: it looks like there's at least one historical implementation (HP-US) that defines MAP_ANONYMOUS but not MAP_ANON. I've applied the patch below. Thanks, Michael -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Linux/UNIX System Programming Training: http://man7.org/training/
